Hypertension is divided into two main categories: primary hypertension (no definite cause, etiology) and secondary (with a definite etiology). Primary accounts for 90-95% and secondary accounts for about 5-10%. Secondary hypertension can be completely cured if the cause is removed, and there is no need for long-term or even lifelong medication as in the case of primary hypertension. So what are the common secondary hypertension? 1, renal substantial hypertension: mostly seen in chronic nephritis, nephropathy. 2, renal vascular hypertension: mostly seen in renal artery disease such as: congenital stenosis and malformation of the renal artery, aortitis. 3, endocrine hypertension: (1) primary aldosteronism; (2) pheochromocytoma; (3) adrenocorticotrophic hypertension. These three diseases are mostly seen in adrenal hyperplasia, tumors, or other parts of the tumor that can be divided into aldosterone, cortisol, catecholamines and other blood pressure-raising substances, etc. 4, aortic constriction: often due to congenital or acquired diseases. 5, other diseases such as: hyperemesis, hyperthyroidism, etc.